Wire-cutting solderless connector



Alg- 24, 1965 E. E. LEACH 3,202,957

WIRE-CUTTING SOLDERLESS CONNECTOR Filed April 30, 1962 /Z` 23 l i j 5T 75 ,477 /QNEXS United States Patent O Fice 3,202,957 WIRE-CUTTING SOLDERLESS CONNECTOR Edward E. Leach, White Bear Lake, Minn., assignor to Minnesota Mining and ManufacturingCompany, St. Paul, Minn., a corporation of Delaware Filed Apr. 30, 1962, Ser. No. 191,068 4 Claims. (Cl. 339-98) This invention is concerned with solderless connectors for small wires as used in communications circuits and is in the nature of an improvement over the type of connector described in U.S. Patent No. 3,012,219.

In that prior art patent there is described a connector having a channelor U-shaped connecting element fitting into a correspondingly Yslotted 'wire-supporting base. The two legs of the U-shaped element are provided with slots in line with the wire-positions. When forced over the inserted and supported wires and into the slotted base, the slotted legs form permanent resilient conductive connection with the wires. Stripping of insulation and soldering of connection are made unnecessary.

It sometimes happens that individual wires may not be inserted into these prior art connectors to a distance sufficient to be contacted by the connecting element when the connector is crimped to form the connection; in which case the short wire pulls loose and the connection must be re-made. To conserve space within juncture boxes or the like, wire-ends are ordinarily pre-cut to minimum length required for the splice; but if not carefully measured, the wire-end may be found to be too short for convenient spilicing. Removal of surplus wire after forming the connection may leave conductive ends exposed, necessitating application of an insulating tape or cap. In all such cases, additional time is required in making an effective connection.

The present invention avoids these and other defects and deficiencies of prior art connectors and methods, and makes possible the simultaneous inter-connection of insulated small conductors and removal of undesired terminal portions of said conductors to provide a permanent well-insulated solderless joint or splice having no protruding Wire-ends and with a minimum of time and effort.

In the drawing:

FIGURE 1 is a plan view and FIGURES 2, 3 and 4 are side elevation and right and left end elevations respectively (relative to the position of FIGURE 1) of a connector in open position;

FIGURES 5-9 are sectional elevations as indicated in connection with FIGURE 1;

FIGURES -13 are partial views of alternative wirecutting structure; and

FIGURE 14 is a view in perspective of a connector element particularly useful in making in-line splices.

The connector 10 consists essentially of a base 11 and a connector element 12. The base, normally of hard plastic insulating material, is provided with longitudinal tubular wire-receiving channels 19 and with channels 20, 21 at right angles thereto for reception of legs 13 and 14 of a resilient conductive metallic connector element 12. A recess 22 for the central plate 15 joining the legs 13 and 14, and a recess 23 for the orienting tab 16 extending from'one edge of the plate 15, are also provided in the base 11.

The legs 13 and 14 fit closely within the channels 20 and 21, in the closed position shown in FIGURES 7 and 9, with a minimum of clearance at the fiat sides so that wires lying within the channels 19 are fully supported at both sides of the legs.

The edges of legs 13 and 14 are slightly tapered outwardly from the plate t-o the half-moon indentation-s 24 (FIGURE 7) and then slightly inwardly to the free 3,262,957 Patented Aug. 24, 1965 corners. The channels 20 and 21 likewise taper slightly away from the center-line as they increase in depth. The structure permits frictional retention of the element 12 within the base 11 when placed with the half-moon indentations at the corners .25 of the channel, while at the same time permitting unrestricted resilient spreading of the slotted leg 13 as it is forced into the channel and onto the wire conductors in completing a connection.

The opposing jaws defining the slots 17 in leg 13 of connector element 12 are substantially parallel over the inner closed portion of the slot and gradually divergent toward the outer end. The fiat faces of these jaws `displace the insulating covering and make firm resilient sliding contact with the metallic conductor of the Wire. A permanent connection is maintained by the resiliency ofthe sheet metal of the plate 13.

In contrast, plate 14 is provided with sharp beveled edges at the notches 18, these edges being so located that they cause complete severing of the wire as the connector element 12 is forced into position within the base 11.

Various alternative cutting edges are illustrated in FIGURES 10-13, and others will be readily apparent. The edge may be beveled on one or both sides of the plate, but an outside bevel as indicated for the notches of leg 14 is ordinarily preferred as being less likely to cause displacement of the wire-'segment between the two legs 13 and 14 during the cutting action.

The connector element 26 illustrated in FIGURE 14 is particularly useful as a replacement for element 12 of FIGURES 1-4 in making line splices. The two Wireends are inserted into the openings 19 from opposite ends of the base and pulled taut, leaving the excess wire hanging from the connector. The element 26 is then forced into place, to make permanent connection between the two conductors and simultaneously to sever the two unwanted end portions which are then discarded. The insulating plastic base conceals and protects the cut ends. No measuring, cutting or wire-stripping is involved. A permanent and well-protected connection is produced with a minimum of time and effort.

It will be appreciated that the connector element may and preferably will .be provided with an insulating cap or coating; that suitable plastic sealants, e.g. silicone greases, may be placed within the connector to impart Waterproofness to the connection; that the metal components may be of any suitably hard, tough and resilient metal and may be plated or otherwise finished if desired, and that various other non-inventive modifications may be included. v

What is claimed is as follows:

1. A wire-connector comprising: a base having openended wire-receiving passages defining parallel wire-supporting surfaces, said base being doubly grooved to provide a pair of parallel grooves extending across said surfaces, each of said grooves being dened by a pair of parallel closely-spaced side walls perpendicular to said supporting surfaces and a pair of inwardly divergent end walls; and a generally U-shaped resilient conductive connector member having a first leg, a second leg, and a connecting base, each said leg being outwardly tapering from said base and indented at both edges at a common distance from said base and at an area of greatest leg width, said` connector member being in position for said legs to be pressed into said grooves and said legs being of appropriate dimensions essentially to provide sliding contact with the side walls and spaced relationship with the bottom and end walls thereof, and said member being releasably retained in said position by contact between the indent surfaces of said legs and the exposed corners of said end walls; at least one of said legs being slotted to receive and make resilient permanent contact with a wire supported on'a corresponding wiresupporting surface, and the other of said legs having a corresponding cutting edge for severing a Wire supported on the same wire-,supporting surface.

2. The wire-connector of claim l in which the forward first leg of the connector member is slotted, and the rearward second leg has a cutting edge, in line with each of the parallel wire-receiving surfaces. v

3. The Wire-connector of claim 1 in which the first leg of the ,connector member is slotted in line with a first wire-.receiving surface and has a cutting edge in line with a second Wire-receiving surface, and the second leg conversely is slotted inline with said irst surface and has a cutting edge in line with said second surface.

4. A wire-connector comprising: a base having openended wire-receiving passages defining parallel wire-supporting surfaces, said base being doubly grooved to provide a pair of parallel grooves extending across said surfaces, each of said grooves being defined by a pair of parallel closely-spacedfside walls perpendicular tofs'aid supporting surfaces and a pair of inwardly divergent end Walls; and a generally U-shaped resilient conductive conn nector member having a first leg,` a second leg, and a connecting base, each said leg being outwardly tapering from said base to an area of greatest leg width at a common distance from said base, said connector member being in position for said legs to be pressed into said grooves and said legs being of appropriate dimensions yessentially to provide sliding contact withthe side walls responding wire-supporting surface, and the other of said` legs having a corresponding cutting edge for severing a Wire supported on the same wire-supporting surface.

. References Cited bythe Examiner UNITED vSTATES PATENTS 2,623,092 A12/52 Miller e 339-97 X 2,651,768 9/53 Oortgijsen -339-97 X 2,802,083 8/ 57 Lapeyre.

3,012,219 12/61 Levin 'et al. 339-98 JOSEPH D. SEERS, Primary Examiner. ALBERT H. KAMPE, Examiner. 

1. A WIRE-CONNECTOR COMPRISING: A BASE HAVING OPENENDED WIRE-RECEIVING PASSAGES DEFINING PARALLEL WIRE-SUPPORTING SURFACES, SAID BASE BEING DOUBLY GROOVED TO PROVIDE A PAIR OF PARALLEL GROOVES EXTENDING ACROSS SAID SURFACES, EACH OF SAID GROOVES BEING DEFINED BY A PAIR OF PARALLEL CLOSELY-SPACED SIDE WALLS PERPENDICULAR TO SAID SUPPORTING SURFACES AND A PAIR OF INWARDLY DIVERGENT END WALLS; AND A GENERALLY U-SHAPED RESILIENT CONDUCTIVE CONNECTOR MEMBER HAVING A FIRST LEG, A SECOND LEG, AND A CONNECTING BASE, EACH SAID LEG BEING OUTWARDLY TAPERING FROM SAID BASE AND INDENTED AT BOTH EDGES AT A COMMON DISTANCE FROM SAID BASE AND AT AN AREA OF GREATEST LEG WIDTH, SAID CONNECTOR MEMBER BEING IN POSITION FOR SAID LEGS TO BE PRESSED INTO SAID GROOVES AND SAID LEGS BEING OF APPROPRIATE DIMENSIONS ESSENTIALLY TO PROVIDE SLIDING CONTACT WITH THE SIDE WALLS AND SPACED RELATIONSHIP WITH THE BOTTOM AND END WALLS THEREOF, AND SAID MEMBER BEING RELEASABLY RETAINED IN SAID POSITION BY CONTACT BETWEEN THE INDENT SURFACES OF SAID LEGS AND THE EXPOSED CORNERS OF SAID END WALLS; AT LEAST ONE OF SAID LEGS BEING SLOTTED TO RECEIVE AND MAKE RESILIENT PERMANENT CONTACT WITH A WIRE SUPPORTED ON A CORRESPONDING WIRESUPPORTING SURFACE, AND THE OTHER OF SAID LEGS HAVING A CORRESPONDING CUTTING EDGE FOR SEVERING A WIRE SUPPORTED ON THE SAME WIRE-SUPPORTING SURFACE. 